South Sudan has agreed to allow 4,000 additional UN peacekeepers to enter the country, after first rejecting the regional protection force as a breach of national sovereignty.

The announcement late on Sunday came after a meeting in the capital, Juba, between President Salva Kiir and ambassadors from the UN Security Council's 15 member states.

"The transitional government of national unity gives its consent for the deployment of the regional force," the government and the security council said in a joint statement, which was read out by Martin Elia Lomoro, the South Sudanese cabinet affairs minister.

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The threat of an arms embargo on South Sudan loomed over the meeting amid warnings by the Security Council, which had approved the deployment of the protection force in mid-August, that it would pursue such action if the government in Juba did not accept the additional peacekeepers.

Kiir had previously said that the deployment of the peacekeeping force was a violation of South Sudan's sovereignty. 

A force of some 12,000 UN peacekeepers is already in the country, and South Sudan has been wary of giving it more authority amid ongoing clashes with opposition forces.

Hybrid court

Protecting civilians has become a critical issue for UN peacekeepers following fighting that erupted in Juba in July between forces loyal to Kiir and opposition leader Riek Machar, threatening to send the world's youngest country back to all-out civil war.

Hundreds were killed and thousands were displaced, while Machar, a former first vice president, fled after the outbreak of violence. 

Both civilians and foreigners, including aid workers, were targeted in the July chaos by soldiers who raped women and girls, conducted mock executions and forced people at one hotel compound to watch as they executed a local journalist.

According to Sunday's joint statement, South Sudan has also committed to implementing a hybrid court to investigate war crimes. 

Both government and rebel forces have been accused of widespread abuses in the recent fighting and during the civil war that began in December 2013 between supporters of Kiir and Machar. 

South Sudan crisis: UN pushes for protection force

Source: Agencies